/* * Copyright (c) 2005 David Xu * Copyright (c) 2003 Daniel M. Eischen * Copyright (c) 1995-1998 John Birrell * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. All advertising materials mentioning features or use of this software * must display the following acknowledgement: * This product includes software developed by John Birrell. * 4. Neither the name of the author nor the names of any co-contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. * * $FreeBSD: src/lib/libpthread/thread/thr_create.c,v 1.58 2004/10/23 23:28:36 davidxu Exp $ * $DragonFly: src/lib/libthread_xu/thread/thr_create.c,v 1.4 2005/05/07 09:29:46 davidxu Exp $ */ #include #include #include #include #include #include #include #include #include #include #include #include "thr_private.h" #include "libc_private.h" struct start_arg { struct pthread *thread; volatile umtx_t started; }; static void free_thread(struct pthread *curthread, struct pthread *thread); static int create_stack(struct pthread_attr *pattr); static void free_stack(struct pthread *curthread, struct pthread_attr *pattr); static void thread_start(void *); __weak_reference(_pthread_create, pthread_create); int _pthread_create(pthread_t * thread, const pthread_attr_t * attr, void *(*start_routine) (void *), void *arg) { struct start_arg start_arg; void *stack; sigset_t sigmask, oldsigmask; struct pthread *curthread, *new_thread; int ret = 0, locked; _thr_check_init(); /* * Tell libc and others now they need lock to protect their data. */ if (_thr_isthreaded() == 0 && _thr_setthreaded(1)) return (EAGAIN); curthread = tls_get_curthread(); if ((new_thread = _thr_alloc(curthread)) == NULL) return (EAGAIN); if (attr == NULL || *attr == NULL) /* Use the default thread attributes: */ new_thread->attr = _pthread_attr_default; else new_thread->attr = *(*attr); if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { /* inherit scheduling contention scope */ if (curthread->attr.flags & PTHREAD_SCOPE_SYSTEM) new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; else new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; /* * scheduling policy and scheduling parameters will be * inherited in following code. */ } if (_thread_scope_system > 0) new_thread->attr.flags |= PTHREAD_SCOPE_SYSTEM; else if (_thread_scope_system < 0) new_thread->attr.flags &= ~PTHREAD_SCOPE_SYSTEM; if (create_stack(&new_thread->attr) != 0) { /* Insufficient memory to create a stack: */ new_thread->terminated = 1; _thr_free(curthread, new_thread); return (EAGAIN); } /* * Write a magic value to the thread structure * to help identify valid ones: */ new_thread->magic = THR_MAGIC; new_thread->start_routine = start_routine; new_thread->arg = arg; new_thread->cancelflags = PTHREAD_CANCEL_ENABLE | PTHREAD_CANCEL_DEFERRED; /* * Check if this thread is to inherit the scheduling * attributes from its parent: */ if (new_thread->attr.sched_inherit == PTHREAD_INHERIT_SCHED) { /* * Copy the scheduling attributes. Lock the scheduling * lock to get consistent scheduling parameters. */ THR_LOCK(curthread); new_thread->base_priority = curthread->base_priority; new_thread->attr.prio = curthread->base_priority; new_thread->attr.sched_policy = curthread->attr.sched_policy; THR_UNLOCK(curthread); } else { /* * Use just the thread priority, leaving the * other scheduling attributes as their * default values: */ new_thread->base_priority = new_thread->attr.prio; } new_thread->active_priority = new_thread->base_priority; /* Initialize the mutex queue: */ TAILQ_INIT(&new_thread->mutexq); TAILQ_INIT(&new_thread->pri_mutexq); /* Initialise hooks in the thread structure: */ if (new_thread->attr.suspend == THR_CREATE_SUSPENDED) new_thread->flags = THR_FLAGS_SUSPENDED; new_thread->state = PS_RUNNING; /* * Thread created by thr_create() inherits currrent thread * sigmask, however, before new thread setup itself correctly, * it can not handle signal, so we should masks all signals here. */ SIGFILLSET(sigmask); __sys_sigprocmask(SIG_SETMASK, &sigmask, &oldsigmask); new_thread->sigmask = oldsigmask; /* Add the new thread. */ _thr_link(curthread, new_thread); /* Return thread pointer eariler so that new thread can use it. */ (*thread) = new_thread; if (SHOULD_REPORT_EVENT(curthread, TD_CREATE)) { THR_THREAD_LOCK(curthread, new_thread); locked = 1; } else locked = 0; /* Schedule the new thread. */ stack = (char *)new_thread->attr.stackaddr_attr + new_thread->attr.stacksize_attr; start_arg.thread = new_thread; start_arg.started = 0; ret = rfork_thread(RFPROC | RFNOWAIT | RFMEM | RFSIGSHARE, stack, (int (*)(void *))thread_start, &start_arg); __sys_sigprocmask(SIG_SETMASK, &oldsigmask, NULL); if (ret >= 0) { /* * Wait until new thread get its thread id, so we can * send signal to it immediately after we return. */ while (start_arg.started == 0) _thr_umtx_wait(&start_arg.started, 0, NULL, 0); ret = 0; } else { ret = EAGAIN; } if (ret != 0) { if (locked) THR_THREAD_UNLOCK(curthread, new_thread); _thr_unlink(curthread, new_thread); free_thread(curthread, new_thread); (*thread) = 0; ret = EAGAIN; } else if (locked) { _thr_report_creation(curthread, new_thread); THR_THREAD_UNLOCK(curthread, new_thread); } return (ret); } static void free_thread(struct pthread *curthread, struct pthread *thread) { free_stack(curthread, &thread->attr); curthread->terminated = 1; _thr_free(curthread, thread); } static int create_stack(struct pthread_attr *pattr) { int ret; /* Check if a stack was specified in the thread attributes: */ if ((pattr->stackaddr_attr) != NULL) { pattr->guardsize_attr = 0; pattr->flags |= THR_STACK_USER; ret = 0; } else ret = _thr_stack_alloc(pattr); return (ret); } static void free_stack(struct pthread *curthread, struct pthread_attr *pattr) { if ((pattr->flags & THR_STACK_USER) == 0) { THREAD_LIST_LOCK(curthread); /* Stack routines don't use malloc/free. */ _thr_stack_free(pattr); THREAD_LIST_UNLOCK(curthread); } } static void thread_start(void *arg) { struct pthread *curthread; struct start_arg *start_arg = arg; curthread = start_arg->thread; curthread->tid = _thr_get_tid(); tls_set_tcb(curthread->tcb); start_arg->started = 1; _thr_umtx_wake(&start_arg->started, 1); THR_LOCK(curthread); THR_UNLOCK(curthread); /* Thread was created with all signals blocked, unblock them. */ __sys_sigprocmask(SIG_SETMASK, &curthread->sigmask, NULL); if (curthread->flags & THR_FLAGS_NEED_SUSPEND) _thr_suspend_check(curthread); /* Run the current thread's start routine with argument: */ pthread_exit(curthread->start_routine(curthread->arg)); /* This point should never be reached. */ PANIC("Thread has resumed after exit"); }